Circular knitting machine



Dec. 7, 1937. E, DEANS ET AL 2,101,494

CIRCULAR KNITTING MACHINE Filed March 4, 1936 3 Sheets-Sheet 1 I "I, l

Dec. 7, 1937. F. E. DEANS ET AL 2,101,494

CIRCULAR KNITTING MACHINE Filed March 4, 1956 3 Sheets-Sheet 2 1937. F.E. DEANS ET AL 2,101,494

CIRCULAR KNITTING MACHINE Filed March 4, 1936 5 Sheets-Sheet 3 4m A 1 mmm PM *N 237. \NWN 1. u 1 ,6 I n N 4Q %WN ma Patented Dec. 7, 1937 UNITEDSTATES PATENT OFFICE CIRCULAR KNITTING MACHINE ompany Application March4, 1936, Serial No. 67,162 In Great Britain March 14, 1935 3 Claims.

This invention is concerned with improvements in or relating to circularknittingv machines.

In application No. 667,444 filed April 22nd, 1933 there is disclosed aknitting machine which is arranged to knit a draw thread into thefabric, between adjacent articles of a string of articles knitted by themachine, to facilitate the subsequent separation of the articles fromone another by withdrawal of the draw thread from the fabric. In saidmachine the draw thread is knitted at a feed point which is additionalto the main feed point of the machine.

In British Patent No. 400,623, there is disclosed (see Figures 7 and 8of the drawings-of said patent) an arrangement whereby at the saidadditional feed point, there is provision for the knitting of a drawthread as above mentioned and also for the knitting of one layer of aFrench welt, the yarn for the French welt being supplied from a secondyarn-feeder provided for that purpose.

In a machine embodying features of the present invention, the secondyarn-feeder above referred to is utilized to feed yarn to one or bothsets of the needles at the additional feed point simultaneously with thefeeding of yarn to the same set or sets of needles at the main feedpoint, with the result that the knitted fabric (plain or ribbed as thecase may be) is composed of two helices of yarn, which yarns may be of acontrasting nature, say differing in colour.

In the knitting of a hose or half-hose by a machine accordingto saidBritish Patent No. 400,623, a series of operations involving theintroduction and withdrawal of the stitch cam of the additional feedpoint into and from its working position-each of which events occurs intwo separate stages-and the movements of the two yarn-feeders of thatfeed point into and out of feeding position, has to occur in a definiteorder and in a definite timing in relation to the rotation of the needlecylinders and to other operations performed by the machine. This seriesof operations is effected by an operating mechanism which starting froman initial position operates said stitch cam, yarn feeders and threadtrapper and cutter devices associated with the yarn feeders, ina seriesof steps. At the completion of said series of steps, the operatingmechanism automatically ceases.to operate. The series of operationsabove referred to occurs during the knitting of a relatively smallportion of the hose or the like i. e. that portion of the hose in thegeneral neighbourhood of the welt. In a machine of the present inventionhowever the sec ond yam feeder has movements into and out of feedingposition at relatively widely separated portions of the hose. Forinstance, the second yarn feeder moves into feeding position for theknitting of the leg portion of the hose from yarn fed from both feedpoints, moves out of feeding position for the knitting of the heel pouchfrom yarn fed only at the main feed point, moves again into feedingposition for the knitting of the foot portion from the said two yarns,and finally 10 moves out of feeding position for the knitting of the toepouch from yarn fed only from the main feed point. The series of stepsin which the devices at the additional feed point are operated is thusformed into a plurality of sections brought about by pauses in theoperative movements of said operating mechanism. These pauses areeffected automatically, the operating mechanism starting and stoppingits operative movements at the beginning and end, respectively, of each00 of the sections. Now, if the operator found it necessary, say byreason of breakage of yarn, to start the knitting of a fresh articlebefore the knitting of the preceding article in the string was finished,the operating mechanism for the devices at the additional feed point, insuch circumstances, would in all probability not be in its initialstarting position, and consequently would be out of step with the restof the machine when the machine wasstarted for the knitting of the newarticle. With a view to preventing such a situation arising, the presentinvention provides a correcting mechanism which returns the operatingmechanism to its initial position if it has accidently been displacedtherefrom and therefore not in step with the rest of the machine.

In application No. 713,732 filed March 2nd, 1934 there is described amethod of anchoring the ends of an additional helix of yarn which isknitted into the fabric at a portion thereof, from yarn supplied at anadditional feed point, the ends of the additional helix being knittedinto the fabric at the main feed point. In knitting machines as usuallyconstructed and in cases in which the knitting of an additional helix isto stop just prior to the knitting of a heel or toe pouch, it is notpossible to anchor the finishing end of the additional helix by themethod above referred to for the reason which will now appear.Immediately preceding the knitting of a pouch, 0 the needles of aboutone half the needle circle are rendered inoperative, the sliders forthese needles having-for this purpose long butts which can engage a cambrought into action at that time which moves the needles to non-knittingposition. The sliders for the rest of the needles, i. e. those which areconcerned in the knitting of the pouch, have short butts which are notlong enough to engage the cam just referred to and consequently are notaffected by it. In the machine described in said British Patent No.400,623, the stopping of the knitting at the additional feed point isdone in two stages. In the first stage, the stitch cam (or a bolt camassociated with the stitch cam) at that feed point, while the long buttsare being acted upon by it, is moved outwardly from the needle cylindera distance suflicient to permit the short butts later on to pass itunaffected but not suflicient for it to lose control of the long butts.At the second stage, the stitch cam is moved fully outward, out of rangeof the long butts, while the short butts are passing it. From theforegoing it will be apparent that the last needle to engage the stitchcam and therefore to knit at the additional feed point, is a needleassociated with a long-butt slider, which needle is then moved tonon-knitting position by the cam aforesaid acting upon the long butt ofits slider. Hence this needle and the long-butt-slider needles adjacentto it no longer knit and the loose end of the yarn fed from and severedat the additional feed point cannot therefore be knitted into the fabricat the main feed point as required by the said method.

To obviate the above difliculty, the present invention provides anarrangement in which between the long-butt sliders and the short-buttsliders there are situated a. few (say six or eight) sliders havingbutts of medium length and the cam which engages the long-butt slidersto move their needles to non-knitting position for the operation ofpouch formation, is adapted (for instance by being made narrower thanusual) to permit the medium-butt sliders to pass it without beingengaged by it. The medium butts, however, are long enough to engage thestitch cam at the additional feed point when the stitch cam is in thefirst of its two stages of withdrawal from operative position. Hence, atthis time, the needles associated with the medium-butt sliders will knitat the additional feed point, and as they will not be moved tonon-knitting position by the cam aforesaid, the loose yarn end held bythem will be knitted into the fabric at the main feed point.

A construction of mechanism, illustrative of the present invention, willnow be described with the aid of the accompanying drawings, and by wayof example will be considered as applied to a machine of the kinddescribed in .said British Patent No. 400,623.

In the drawings:-

Figure 1 is an elevation of part of the machine showing the lower orplain needle cylinder and devices associated with an additional feedpoint including a stitch cam for that needle cylinder;

Figure 2 is a plan of parts seen in Figure 1;

Figure 3 is an elevation of mechanismconcerned in the operation of thedevices at the additional feed point;

Figure 4 shows in plan and partly in section, parts seen in Figure 3;and

Figure 5 is a diagram hereinafter referred to.

The machine described herein will be considered as arranged to knitribbed hose or half-hose in the usual string formation, with a drawthread included between adjacent articles, each article having the usualtype of welt, and with its sole hose including the sole, but not ofcourse the pouches, will be knittedin two helices of yarn supplied fromboth feed points.

The machine to which the present correcting mechanism is applied, isprovided with the customary control drum by rotation of which variouschanges in the knitting operation are brought about, the rotation of thecontrol drum being controlled, as usual, by the main pattern chain (notshown) of the machine, which chain travels in timed relation with therotation of the needle cylinders.

The operating mechanism of the present machine for the devices of theadditional feed point, in general, is similar to the correspondingmechanism described in said British Patent No. 400,623 in connectionwith Figures 7 and 8 of the drawings thereof, and the driving and timingdevices for that mechanism are, in the main, alike in the two machines.

The additional feed point comprises'a stitch cam I4 located in the cambox for the lower or plain needle cylinder I2, a feeder 220 for the drawthread, a feeder 260 for the yarn of the helix that is knitted at thisfeed point, a trapper and cutter device 230 associated with the feeder220, and a similar device 204 associated with the feeder 260.

These devices are operated by a set of cams mounted upon and rotatablewith a shaft 04. The cam 294 operates the stitch cam I4, the cams 234and 280, respectively, operate the feeders 220 and 268, and the cams 256and 202, respectively, operate the trapper and cutter devices 238 and284. In the drawings these cams are shown diagrammatically as plaincircular discs, i. e. no attempt has been made to indicate theperipheral configuration which in practice the cams possess. In thepresent machine the feeder 268 is mounted upon its supporting spindle210 so as to be able to swing in a vertical plane about a pivot 500, aspring 502 serving to press the tail end of the feeder against a camplate 500 which guides the feeding end of the feeder 260 over itscompanion feeder 220, as the feeder 288 moves between feeding and idlepositions.

The driving mechanism for the cam-carrying shaft 94 is shown in Figures3 and 4. This mechanism comprises a ratchet wheel I00 which is operatedby a pawl I02, pivoted at I04 on a lever I06, a spring I00 (Figure 3)tending to maintain the pawl I02 in engagement with the ratchet 'wheel.The lever I06 is pivoted at I09 on a. bracket III! secured to a fixedpart 52. The lever I06 is actuated by a cam II2 through the agency of apush rod I which, as presently will be explained, is moved laterallyinto and out of the path of the cam I I2, so as to start and stop,respectively, the driving action of the cam H2 upon the pawl and ratchetdevice I00, I02. The cam II2 has two rises and falls and is attached toa part of the machine (a bevel gear wheel 0) which revolves at the samespeed as the needle cylinder and so gives two movements to the verticalshaft 94 for each revolution of the needle cylinder when the push rodIll is in the path of the cam H2. The push rod III is mounted to slidein a guideway formed in a lever III which is fixed on a shaft I20,journalled in bearings I22 on a fixed part of the machine frame. Thelever H0 is moved by connections between it and cams on the control drumI26 of the machine one of which cams is shown at I24, so that atpredetermined times it moves the push rod Ill into and out of the pathof the cam H2. The

idle track for the push rod H4 is round the outside of the cam H2. Theconnections between the control drum I26 and the lever II8 comprise alever I28 fixed to the shaft I20, and a push rod I30, which passesthrough an eye in the end of the lever I28 and is operated by the camsI24 on the control drum I26. The push rod I30 operates the lever I28through a spring I32, so that, should the cam I24 come into operation(either when the control drum I26 is being turned by hand, or otherwise)at a time when the push rod I I4 is in its idle track i. e. on the outerside of the cam II2, the push rod II4 will be pressed against the sideof the cam H2 and the spring I32 will be compressed until the end of thecam II2 has passed the push rod II4 when the latter will spring into thetrack of the cam II2. A spring I34 serves to return the push rod II4 toits idle track after the required number of turning movements has beengiven to the vertical shaft 94 by the mechanism just described.

In the present machine, the cam-carrying shaft 94 makes one completerevolution during the knitting of each article, and the ratchet wheelI00 which is driven by the pawl I02, has eighteen teeth (pins). The camson the shaft 94 which operate the two feeders 220, 268, the two trapperand cutter devices 238, 284, and the stitch cam I4 are of singleformation, i. e. they are so formed as to impart but one completeoperation or series of operations appropriate to a single article uponthe devices they actuate, during each revolution of the shaft 94.

During the knitting of an article the operating mechanism for thedevices at the additional feed point acts as follows: The first movementof the shaft 94 is idle, that is to say, the shape and disposition ofthe cams upon it are such that no movement is given by the cams to thedevices which they operate. At this time the long butt needle-slidersare passing the position of the stitch cam I4 which accordingly must notbe moved inwardly otherwise these butts would be damaged. The secondmovement of the shaft 94 causes the stitch cam I4 to be given its firststage of inward movement which occurs during passage of the short buttneedle-sliders past the stitch cam position, thus bringing the stitchcam I4 into the path of movement of the long butts but permitting theshort butts to pass it unaffected. At this time the draw thread feeder220 is moved into feeding position in readiness for the draw thread tobe taken by the needles of the long butt sliders when these are actedupon by the stitch cam I4. At the third movement of the shaft 94, thestitch cam I4 is given the second stage of its inward movement while thelong butts are being acted upon by it, so that the stitch cam I4 can actalso upon the short butts when these reach this stitch cam. And thetrapper 238 is {opened to release the end of the draw thread which isnow being knitted into the fabric at the additional feedpoint by needlesof the bottom cylinder while rib-knitting is being efiected at the mainfeed point. The fourth movement of the shaft 94 is an idle one. On thefifth movement of shaft 94 the stitch cam I4 is given the first stage ofits outward movement while the long butts are being acted upon by it. Onthe sixth movement of shaft 94, the stitch ,cam I4, while the shortbutts are passing its position, is given the second stage of its outwardmovement, and at the same time the draw thread feeder 220 moves intoinoperative position-and the draw thread is trapped and cut by thetrapper and cutter device 238. This completes the operation of theknitting of the draw thread into the fabric.

The machine next forms the welt in the usual manner at the main feedpoint.

After the welt is knitted, the shaft 94 is given its seventh movementwhich, however, is an idle one. The eighth movement of the shaft 94gives to the stitch cam I4 its first stage of inward movement, while theshort butts are passing its position, and also brings the secondyarn-feeder 268 into position to feed yarn to the needles of the longbutt sliders when these butts in their turn reach and are acted upon bythe stitch cam I4. The ninth movement of the shaft 94 gives to thestitch cam I4 the second stage of its inward movement in readiness toengage the short butts when these arrive at that cam, and the trapper284 is opened to release the end of the yarn fed from the secondyarn-feeder 268. The tenth movement of shaft 94 is idle. The fabric isnow being knitted in two helices, one derived from yarn supplied at themain feed point and effected at both feed points, the machine being iprovided, of course, at the additional feed point with a rib-stitch camin the upper needle cylinder which cam is automatically adiusted intooperative position when rib-knitting at that feed point is to beperformed.

Rib-knitting now continues at both feed points until the heel pouch isto be knitted. At about this time the shaft 94 is given its eleventhmovement during which the stitch cam I4 is given the first stage of itsoutward movement as the long butts are being acted upon by it. Thetwelfth movement of shaft 94 gives to the stitch cam l4 the second stageof its outward movement where it is out of range of all the butts andconsequently knitting at the additional feed point ceases. During thismovement of the shaft 94 the said second feeder 268 is moved intoinoperative position and the yarn issuing from it is trapped and cut bythe trapper and cutter device 284.

As before explained, in order to anchor at the main feed point this endof the yarn supplied from the second feeder at the additional feed pointa few needle sliders (as shown in the diagram, Figure 5, of the needlecircle) having medium-length butts 506 are inserted between thelong-butt sliders 508 and short-butt sliders 5I0, which medium-lengthbutts 506 can engage the stitch cam of the additional feed point whenthat cam is in the first stage of its outward movement, but are not longenough to engage'the cam aforesaid which, at the appropriate time, isautomatically adjusted into position to engage the long-butt sliders 508and move their needles to non-knitting position.

After the knitting of the heel pouch by the usual reciprocatory movementof the machine, rotary knitting is resumed for the foot part of thearticle with yam supplied from both feed points, the starting ofknitting at the additional feed point being effected by movementsthirteen to sixteen of the shaft 94, which movements cor respond withthe seventh, eighth, ninth and tenth movements of that shaft andaccordingly need not be described.

When the toe pouch is to be knitted, the shaft 94 makes its seventeenthand eighteenth movements, which correspond with its eleventh and twelfthmovements already described, to suspend knitting at the additional feedpoint. The article is then completed by the knitting of the toe pouch inthe usual manner. It will be understood that the ends of the yarn fedfrom the additional feed point during the knitting of the foot part ofthe article are also anchored in the fabric by the method hereinbeforereferred to.

From the foregoing it will be appreciated that the eighteen movements ofthe shaft 94 are broken up into sections by pauses in those move ments.In order to ensure that the movements constituting each section shall becompleted even though the control drum I26 is moved on so that the pushrod I30 is free to fall off the end of the cam I24 which operated it,the following mechanism is providedz-The ratchet wheel I has formed init, a series of notches I36 and a tooth I30 at one end of a bell-cranklever I40 is adapted to engage these notches. The other end I42 of saidlever lies alongside (i. e. below as seen in Figure 4) a projection I44on the lever III if the push rod I I4 in that lever is in its idletrack. The lever I40 is pivoted at I46 on the bracket I I0 and the toothI30, for the purpose of adjustment may, as shown, be formed on a blockI40 adjustably secured to the lever end by a screw I50. In the positionjust described the vertical shaft 94 cannot be rotated as the projectionI44 prevents the lever I40 from being turned in a direction which wouldremove the tooth I36 from the notch I36 with which it is engaged. Whenthe lever H6 is moved in the operative position (as shown in Figures 3and 4) by the action of a cam I24 on the control drum I26, the firstmovement of the ratchet wheel I00 places the end I42 of the leverI40-behind (i. e. as shown in Figure 4) the projection I44. lhe lever H6is thereby held in its operative position, irrespective of the positionof the control drum I26 until the tooth I36 on the lever I40 falls intoa notch I36 by the action of a spring I52. The push rod H4 is thensprung back to its idle track by the action of the spring I34. A springI54 (Figure 4) connected to the lever I06 and to a fixed part I56 tendsto keep the lever pressed against the push rod II4.

From the foregoing it will be appreciated that provided the shaft 94 isin its correct angular position in relation to its driving mechanism(which comprises the cam H2 and the pawl I02 operated by that cam) thereis but little probability that the timing of the movements of the shaft94 in relation to the timing of other associated devices of the machine,will be disturbed. The timing of the said driving mechanism in relationto the rotation of the needle cylinders, is taken care of by theprovision of a curved plate II3 (Figure 3) which is attached to the camH2 and closes one of the gaps between the contiguous ends of the twoportions of the cam H2.

In order to ensure that the shaft 94 is in its correct starting positionbefore the knitting of an article by the machine is begun, the followingcorrecting mechanism is provided which will automatically return theshaft to its starting position should it have been accidentallydisplaced therefrom.

This correcting mechanism comprises a springcontrolled correcting rod6I2 similar to the rod I30 and located below and somewhat to one side ofthe rod I30. One end of the correcting rod 6I2 is adjacent the controldrum I26 and the other end of this rod is connected by an adjustablevertically-disposed link II4 to one end of a lever 6I6 arranged to turnabout a pivot pin 6I6 carried on the bracket H0. The other end of thislever is upturned to form a cam follower arranged in the path of a cm620 on the underside of the ratchet wheel I00 on the shaft 94. Securedto the shaft I20 and arranged alongside the lever I26 is a depending arm622, the lower end of which is Just above a collar 624 on the correctingrod 5I2. This collar 624 is loose on the rod 5I2 but is backed up by aspring 526 that encircles the rod and bears against a collar 528 fast tothe rod. The correcting rod 5I2 is moved endwise at times by a cam 630on the control drum I26.

If the shaft 94 is in its correct starting position, the correcting rod5I2 will merely be moved endwise idly against the action of its spring6I3 by the cam 530 on the control drum I26. But if the shaft 94 isdisplaced from its starting position, the cam 520 on the ratchet wheelI00 will depress one end of the lever 5I6, thereby raising its other endand lifting the correcting rod 6I2 so as to bring the loose collar 524thereon alongside the free end of the depending arm 622. When thereforethe correcting rod 5I2 is moved endwise by the cam 530 on the controldrum I26, the loose collar 524 on the rod will engage the depending arm522 and, by way of force transmitted by the spring 626 on the rod, willturn the shaft I20 in a direction to bring the push rod I I4 into thepath of the cam I I2 and thereby start the driving mechanism for theshaft 94 into action. The shaft 64 will thus be turned until it arrivesin its starting position wherein the cam 520 on the ratchet wheel I00will have been removed from engagement with the follower of the lever5I6, permitting the lever 5I6 to turn and thereby allow the correctingrod 5I2 to fall into its lower and idle position.

Although in the foregoing description the controlling mechanism has beendescribed as giving various movements to the stitch cam of theadditional feed point, in practice it is preferred to give suchmovements to a pilot cam which, when operative, deflects theslider-butts to the stitch cam proper. Further, this stitch cam itselfis preferably made adjustable for stitch-length variation convenientlyby means of operative connections between it and the mechanism forsimilarly adjusting the stitch cam of the main feed point.

We claim:

1. A knitting machine comprising a stitch cam movable between aneedle-actuating position and an idle position, a plurality of threadfeeders each independently movable between a threadfeeding position andan idle position, thread trapper and cutter devices each associated,respectively, with one of said feeders to trap and cut and to releasethread fed from said thread feeder, operating mechanism for operatingsaid stitch cam, thread feeders, and trapper and cutter devices, whichoperating mechanism during the knitting of an article by the machine ismoved from an initial position in a series of steps formed into sectionsby pauses in the movement of said mechanism at predetermined points inthe operation of the machine, driving means for driving said mechanism,stopping means for automatically stopping the ,driving action of saiddriving means at the end of each of said sections, starting means forstarting said driving action at the beginning of each of said sections.pattern control means, devices on said pattern control means foractuating said starting means, and a correcting mechanism comprising anadjustable element, operative connections between said element and saidoperating mechanism arranged to maintain said element normally inoperative relation with said starting means but to move said element outof such relation when the said operating mechanism is in its initialposition, and, a device on the pattern control means for operating saidelement at a time in the operation of the machine at which the operatingmechanism should be in its initial position, whereby if the relationbetween the pattern control means and the operating mechanism has beendisturbed, the starting means will be actuated by said element and willcause the driving means to drive the operating mechanism into itsinitial position.

2. A knitting machine comprising a stitch cam movable between aneedle-actuating position and an idle position, a plurality of threadfeeders each independently movable between a threadfeeding position andan idle position, thread (rapper and cutter devices each associated,respectively, with one of said feeders to trap and cut and to releasethread fed from said thread feeder, operating mechanism movable from aninitial position in a series of steps for operating said stitch cam,thread feeders, and trapper and cutter devices, pattern control meansfor starting said operating mechanism into operation from said initialposition and for thereafter stopping and restarting said mechanismthereby forming said series of steps into sections, driving means forsaid operating mechanism comprising a continuously moving cam, a pawland ratchet device, and operative connections between said cam anddevice whereby said device is adapted to be driven by said cam, adisconnectable element in said operative connections under control ofsaid pattern control means, a locking device operated by the pawl andratchet device for maintaining said element in connecting position.until each section of said series of steps is complated, and meansoperatively connected with the pawl and ratchet device and also undercontrol of said pattern control means for moving said disconnectableelement into connecting position if the correct positional relationshipof the pawl and ratchet device with the pattern control means isdisturbed.

3. A knitting machine comprising a stitch cam movable between aneedle-actuating position and an idle position, a plurality of threadfeeders each independently movable between a thread-feeding position andan idle position, thread trapper and cutter devices each associated,respectively, with one of said feeders to trap and cut and to releasethread fed from said thread feeder, operating mechanism movable from aninitial position in a series of steps for operating said stitch cam,thread feeders, and trappers and cutter devices, a control drum, devicescarried thereby for starting said operating mechanism into operationfrom said initial position and for thereafter stopping and restartingsaid mechanism thereby forming said series of steps into sections,driving means for said operating mechanism comprising acontinuouslymoving cam, a pawl and ratchet device and operativeconnections between said cam and device whereby said device is adaptedto be driven by said cam, a disconnectable element in said operativeconnections under control of the said devices on the control drum, alocking device operated by the pawl and ratchet device for maintainingsaid element in connecting position until each section of said series ofsteps is completed, a cam driven by said pawl and ratchet device, amember adjustable into and out of operative connection with saiddisconnectable element, operative connections between said last-namedcam and said member for effecting such adjustment of said member, and adevice on the control drum for actuating said member.

FREDERICK EDWARD DEANS. CHARLES FREDERICK MANGER. GEORGE ALFRED BUSWELL.

